Loading fbdev driver solved the problem. Now I got X in full res and screen is detected correctly i only can't change resolution to 1024x768 which is required by some 'blind' users. Help! That's not a big problem but i think you may know the aswer to it.
I have also managed to retrieve Xorg log file when unichrome driver is loaded:
http://pastebin.com/aJ68RLA9xorg.conf file i have used for unichrome is here:
http://pastebin.com/5712vzd9I thought you may want to look at them and suggest something...
Big thanks for Curaga for very accurate diagnosis and all kind people who helped me trace the problem
As I'm new to Linux i will have more and more questions. More enough to hate me